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Energy Vault – Gravitational Batteries

energyvault.com

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Re: Energy Vault – Gravitational Batteries

#31

Post by lordnacho »

kumarvvr wrote: post #11

1 Ton of mass, at 100 m height, holds 0.2778 kWh of energy. 100 tons (3 bricks as per their design) - 27.778 kWH 100 x 100 Tons (300 bricks ) - 27.78 MWH. However, as per their design, not all bricks store the same amount of energy. The lower section of bricks would not be economical. Every Ton of Concrete, on average produces 0.9 Tons of CO2 during its manufacturing process. 1 MWH of electricity generation, on avera…

Couldn't you instead of making solid concrete blocks fill them with junk, using just a little concrete to make the shape right?

Re: Energy Vault – Gravitational Batteries

#32

Post by kumarvvr »

desman wrote: post #20
kumarvvr wrote: post #18

Earlier quoted context omitted.

To be fair, Pumped Storage is really dependent on Geography. It has downstream affects on environment due to having reservoirs where none have been and all. It's powerful, cheap and long lasting, but not easily available. One can't eat the cake and have it too.

Well, this thing also depends on geography. There aren't many places where such a construct would be easy to build: seismic situation, static stability for these enormous weights, winds (it's actually quite funny to see cranes side by side with wind turbines in their commercial)

True, but the choice of available places for cranes is much much higher than pumped storage.

Re: Energy Vault – Gravitational Batteries

#33

Post by lovemenot »

simonebrunozzi wrote: post #16
imtringued wrote: post #2

Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…

I would use depleted uranium for that. Many countries have to store thousands of tons of it, and governments will pay you for storing it. Instead of making it sit idle, you might as well use one of its finest qualities (density).

Let's make Fort Knox fully renewable by storing wind/solar in stacked gold bars.

Re: Energy Vault – Gravitational Batteries

#34

Post by treekogreen »

IanCal wrote: post #27
treekogreen wrote: post #26

Earlier quoted context omitted.

Would a better design not to bore downwards instead of build upwards? This seems like such an over-engineered concept that could be simplified and compartmentalised drastically. There's a whole host of negatives I see in this implementation, not to mention the downsides of erecting a crane-line structure and public opinion. This is a UK company doing what I described above: https://gravitricity.com/ (i have no affili…

Drilling is also complex and expensive. You'd have to go down, reinforce it and deal with pumping at the very least. On the other hand a crane is, well, a pretty small and simple (/well known) thing. It's a crane and a stack of bricks, it doesn't feel particularly over engineered to me. Either may make sense given the surroundings but I don't think building up is an obvious problem

From a personnel safety standpoint (what a catastrophic failure looks like in each case), a unit installation cost standpoint (fabricate x amounts of bricks with x tolerance in the grooves plus a crane with y units of generation on top) and finally from a complexity standpoint of stacking stacking bricks (I assume is not just going to be a stored procedure and include some kind of error correction and monitoring).

I just cant see anything positive about this solution in the slightest. I wouldn't want to be anywhere near that structure. A crane truly is a simple and well known thing but I have tangible knowledge of a large community pushback in the UK where all that was installed was a relatively small turbine on the top of a hill.

Boring and reinforcement (concrete spraying) is a tried and true technology and most importantly its out of sight.

Re: Energy Vault – Gravitational Batteries

#35

Post by baybal2 »

kumarvvr wrote: post #18
desman wrote: post #13

Earlier quoted context omitted.

...and using water instead of concrete. And then you get pumped storage https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... which is reasonably widely used and doesn't attract as much investors' attention as this "innovation"

To be fair, Pumped Storage is really dependent on Geography. It has downstream affects on environment due to having reservoirs where none have been and all. It's powerful, cheap and long lasting, but not easily available. One can't eat the cake and have it too.

Just build water towers. 100m water tower is nowhere near as an extreme engineering as this.

Re: Energy Vault – Gravitational Batteries

#36

Post by dmos62 »

kumarvvr wrote: post #12

I really wish humanity comes up with a good way to store large quantities of electricity (not counting Hydro Batteries). Compressed air in mines is a good alternative, with heat of compression also stored. I am actually looking for ways to make this small scale. As in, creating a storage system for domestic use. In developing countries, average energy usage per house hold, would be not more than 10 kWh per day. Compr…

I've read about using a lot of small cheap containers, like plastic bottles, as compressed air batteries, but can't find the article right now. Apparenly a lot of small containers is a significant improvement over few (or single) large compressed air containers. Many small containers offer better space efficiency, they're cheaper, because you require less pressure (regular plastic bottles v. steel tanks), and their power output is steadier.

Re: Energy Vault – Gravitational Batteries

#37

Post by baybal2 »

Tade0 wrote: post #24
kumarvvr wrote: post #12

I really wish humanity comes up with a good way to store large quantities of electricity (not counting Hydro Batteries). Compressed air in mines is a good alternative, with heat of compression also stored. I am actually looking for ways to make this small scale. As in, creating a storage system for domestic use. In developing countries, average energy usage per house hold, would be not more than 10 kWh per day. Compr…

We already have that in the form of LiFePO4 batteries. They last over 2000+ cycles, use no rare/expensive/conflict minerals and are safe. Also just recently they crossed the $100/kWh barrier in some markets: https://about.bnef.com/blog/battery-pack-prices-cited-below-... An ISO container(40ft) of those can store 10-15MWh. For the cost of the Astravets Nuclear Power Plant in Belarus ($11bln, 2GW) you could have 80GWh…

I came to very much the same conclusion few weeks ago https://news.ycombinator.com/item?id=25651782

The basic math behind the company simply doesn't work. They cannot make money out of it.

Re: Energy Vault – Gravitational Batteries

#38

Post by __alexs »

J-dawg wrote: post #23

I'm quite fascinated about how an idea like this gets as far as somebody founding a company when, as several people here (as well as the linked videos) have argued quite convincingly, it appears to be easily debunked. Are the founders knowingly trying to scam investors? Are they just naive/stupid? Or am I (and the debunkers) being too negative, and this is just the first iteration of an idea that could one day change…

"SoftBank Vision Fund" is all you need to know.

Re: Energy Vault – Gravitational Batteries

#40

Post by riffraff »

baybal2 wrote: post #35
kumarvvr wrote: post #18

Earlier quoted context omitted.

To be fair, Pumped Storage is really dependent on Geography. It has downstream affects on environment due to having reservoirs where none have been and all. It's powerful, cheap and long lasting, but not easily available. One can't eat the cake and have it too.

Just build water towers. 100m water tower is nowhere near as an extreme engineering as this.

a 100m water tower doesn't hold as much energy either does it? It's pretty light compared to concrete, I think.
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